The present invention generally relates to cooling systems, and more particularly to cooling arrangements for electronic systems.
As computers and computing systems increase in processing power and memory size there is a competing goal to provide these capabilities in ever decreasing packaging sizes. However, as the density of the memory and processing components within computing systems increases, heat dissipation becomes an increasingly important design factor. Major sources of heat in such computing subsystems include microprocessors and hard disk drive assemblies. As new workstations and servers are developed they will incorporate multiple hard disk drive assemblies in close proximity to each other, thus posing a significant thermal cooling challenge.
In the past, computer systems of this kind have incorporated within their enclosures cooling devices such as heat sinks, extended surface devices applied directly to disk drive assemblies, and air movers in the form of fans to increase air mass flow rates. Air volume flow rates on the order of 2.5 to 5 liters/second, at a velocity of 2 to 3 meters/second, typically have been required for each microprocessor. Large multi-processor systems and large multi-disk drive systems used in dedicated computer rooms can be cooled by moving air at high mass flow rates with the resulting acoustic noise generally having to be tolerated. On the other hand, multiple processor and multiple disk systems used in office environments must meet more stringent acoustic emission guidelines, regulations, and customer/user requirements. In these cases, cooling the systems by increasing the air mass flow rates is not a practical option.
Efforts have been made in the past to cool electronic systems using a working fluid that undergoes a reversible phase change. In particular, power-dissipating components such as power transistors have been mounted directly to an external panel of such systems. A sealed fluid channel that carries the working fluid is formed in the panel. The working fluid absorbs heat and evaporates in the portion of the fluid channel adjacent to the power transistors. Heat is transferred to other portions of the fluid channel where the gaseous phase cools and the liquid condenses. One of the disadvantages to this approach is the inability to efficiently cool power dissipating components that are not mounted directly on the external panel.
It will be appreciated that there is a need for a system and an apparatus for effectively cooling the heat dissipating components of a computer system without increasing the computer""s enclosure size and cost. A system and an apparatus that address the aforementioned problems, as well as other related problems, are therefore desirable.
The present invention is directed to addressing the above and other needs in connection with cooling electronic components and facilitating the increase of the packing density of integrated components in an electronic system. With the cooling arrangement of the present invention, microprocessor and memory modules incorporated into servers and workstations applications, that dissipate about 150 to 200 watts, each can now be placed in closer proximity to each other thereby increasing processing speed. With the present approach, multiple microprocessor systems (incorporating 32 microprocessors, dissipating about 10 to 12 kilowatts) can now be assembled at lower costs with higher levels of reliability. The present approach could also address the heat dissipation drawbacks of future hard disk drive assemblies that dissipate more than 25 watts each.
According to one aspect of the invention, a cooling arrangement is configured and arranged for cooling an electronic system located within an enclosure, wherein the electronic system includes a plurality of circuit boards having a plurality of integrated circuit elements disposed within a lower portion of the enclosure. The cooling arrangement includes a pump located within the enclosure that has a first and second coolant ports and a heat exchanger that is disposed within a top portion of the enclosure and is coupled to the first coolant port. The cooling arrangement also includes a thermally conductive member having a first surface and a second surface, the first surface being in thermal contact with at least one of the integrated circuit elements. A first cooling plate arrangement having a coolant channel with a first end coupled to the second coolant port and a second end coupled to the heat exchanger is included in the cooling arrangement that is in thermal contact with the second surface of the thermally conductive member. In a related embodiment, the thermally conductive member is part of a circuit module that is disposed on a main system board.
According to another aspect of the invention, an electronic system in combination with a cooling arrangement is located within an enclosure. The system includes a pump located within the enclosure that has a first and second coolant ports and a heat exchanger disposed within a top portion of the enclosure and coupled to the first coolant port. The system also includes a microprocessor circuit module and a memory circuit module disposed within the enclosure, the microprocessor circuit module having a microprocessor contained in a first thermally conductive housing and the memory circuit module having a memory element contained in a second thermally conductive housing. The system further includes a first and second cooling plate arrangement in thermal contact with a first surface of the respective thermally conductive housings, wherein at least one of the cooling plate arrangements has a coolant channel with a first end coupled to the second coolant port and a second end coupled to the heat exchanger.
It will be appreciated that various other embodiments are set forth in the Detailed Description and Claims that follow.